Generally in the window and door industry windows are considered to provide the main function of letting in light to a building. Of late it is desirable to have large windows within the building which improve the room lighting but which do not support structural loads. It is therefore a primary object of the invention to provide a preferably load bearing structural closure for installation within a building which includes a multiplicity of closures (and preferably casement style) to provide an enhanced shared plane assembly. Further and other objects of the invention will become apparent to one skilled in the art by considering the following summary of the invention and the more detailed description of the preferred embodiments illustrated herein.